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The paper reports the results of applying an iterative procedure devised to establish a set of velocity standard stars for monitoring the behavior of the Fick Observatory photoelectric radial-velocity spectrometer. Data obtained during the first three years of observation with this instrument are used to select a set of 200 velocity standard stars brighter than 7th magnitude of spectral types from late F to early M. All velocities have been reduced to the Fick Observatory system.

We describe a relatively simple, but highly effective, approach to the system design and alignment of an all-refractive Offner null corrector and phase-measuring Shack cube interferometer. In addition we outline procedures for fabricating and testing the optical components. Allowable errors for all parameters are determined by a tolerance analysis that separates axisymmetric and residual figure errors. An open construction optics frame provides a high degree of metering flexibility by incorporating simple kinematic mounts that provide adjustment of each lens while also allowing the lens to be removed and replaced with < 2-μm absolute repeatability. Nonaxisymmetric alignment errors are removed by rotating the optics on a high-precision bearing. Axial spacings are measured with contact transducers attached to both ends of an Invar metering rod. Two completed systems have guided the stressed-lap polishing of 1.8-mf/1.0 and 3.5-m f/1.5 aspheric mirrors.